I’d like to share my story, it happened on last night. And please forgive my writing if it is not good, my english is poor though.

Im a new citizen, and on my 27th day in Eve, I figured trading is FUN, I started buying/selling electronic parts, I went through lowsec area and got my cargo ship blowed up, guess what, i got a bounty on my head bcos my ship was empty.
Nevermind, then I searched for higher profit product. From a trading market information website, i found out someone was willing to pay a slave for 5000 isk in Jita, and the slave I bought was only 705 isk, that is a big profit for me. I used all my isk and load up the ship, set destination to Jita. After going through a few stargates, my screen got prompt by Gallente Custom, then I figured I was carrying something illegal. The penality is huge, 9.4mil ! I thought I can continue my trip after paid the fines, but after going through the next stargate, I got prompted by custom again, paid another 9.4mil, and lost all my slaves (or my ship). At that time my balance was -18mil.

With negative balance, I tried to fix it by myself :

Sell valuable items to market, but it didn’t work. I had to paid the selling fee first before I can sell it to others.

Work on missions, but it will take me a long time.

I was thinking to buy Plex and then sell it for isk, lucky I didn’t do it bcos the market does not allow me to sell without isk.

Finally, I posted my problem in the Rookie chat channel, and a white knight named Erneste Ambraelle sent me 20mil. I told him I will pay him back. But he refused, and told me to help another noob in-need. What a good guy I met!

Thank you for reading my story.

BTW, please think about how to fix negative balance, it is odd I cannot sell items in market to the buy order without isk.

While i am your side for your plight the reason for the penalties for negative balance serve a purpose. The most common method or ccp directly punishing a player for eula infractions are a negative balance.

Congrats for learning that certain things are illegal (drugs, slaves) and the game has a Customs and NPC Police force that acts as it should. For the future, show info on items that seem shady, and you should see a Legality tab that explains where they are illegal. You can also set up your Overview list to show NPC Customs ships, and pay attention to where they are (not everywhere), so if you want to smuggle illegal stuff for the big profits, you know which routes to take.

Otherwise, as the other replies have said:

Negative balance is used as punishment by CCP - if you take advantage of an exploit they will remove the exploit ISK from your wallet, making it difficult for that character to trade on the market. The reason why it’s impossible to trade is because you have to pay taxes and broker fees to trade on the market (and contract fees for contracts).

If they remove negative balance from the Customs NPCs, people will just transport drugs with an empty wallet, to negate the effect of the Customs penalty for getting caught, which would likely be an exploit.

Had a related issue, in a mission I looted some slaves from a wreck and was willing to bring them to the starting station to find out how to “free” them - I despise slave trade, but I can’t let them die in space either, so I thought “trashing” them in a station might do the job.
At the very next Minmatar Stargate I also got this message you mentioned - and lost some standing with the Minmatar Republic. So I’m afraid that all my freed slaves have to be jettisoned which customs apparently consider much more human than bringing them home…

they have this system in the game for another reason to if you’re caught buying isk
if you bought 30 billion isk CCP will give you a ban and take 60 billion away from you so you’re 30 billion in the hole

I had the negative balance from customs hit me once to. It sounds like they fixed the annoying bug that went with it though. I had to pay the fine on the spot, but I didn’t have the money because it had sent me negative. The customs ship had me pinned until I could get a stuck tickets submitted.

If they remove negative balance from the Customs NPCs, people will just transport drugs with an empty wallet, to negate the effect of the Customs penalty for getting caught, which would likely be an exploit.